10" TC OEM with 104sq in of port

[Rashaddd 5,000+ posts]

got to be one of the dumbest car audio related things i have seen. why use a 12" port with a 10" sub?
a 4 inch port is fine on a ten, and even a 6 is overkill. hell, i use a 3" port with my 10 and it's fine.

i'm no port-ologist, but doesn't it turn into more of an "IB" or "free air" than a ported box after that much port?

Good lord the whole fvcking point of this thread is that it obviously doesn't, contrary to that popular misconception.

 

[tommyk90 5,000+ posts]

How? If it's tearing a bag up on my fingers, and clearly quite violent, port velocity is high. I would assume high port velocity + high port area = lots of air, no? Smaller port + high port velocity = less air, right? Speed x area = amount of air displaced in a given time frame. If you have the same velocity going through a 3" port, how the hell are you going to move more air (at a given frequency)?

Please correct me.

Unless you are measuring the actual airspeed/density, you have no actual evidence of high port velocity.

Regardless, what the hell does this have to do with anything whatsoever?

 

[Rashaddd 5,000+ posts]

Unless you are measuring the actual airspeed/density, you have no actual evidence of high port velocity.
Regardless, what the hell does this have to do with anything whatsoever?

If I go outside and see a tree blowing over, I'm fairly confident that there are relatively high windspeeds, regardless of whether I actually measure it or not...

What is SPL? Pressure, what is pressure? force/energy, which creates movement of air.

Bigger amounts of air moving is evidence of higher output levels.

Have you ever seen a car doing high numbers without moving any air? Granted with a car there are hundreds of other variables that may restrict the apparent movement of air and velocity of air, which is why some do better hairtricks/etc than others. Frequency also affects it. But when comparing same frequency, same car/setup, more air movement = louder, no?

 

[tommyk90 5,000+ posts]

If I go outside and see a tree blowing over, I'm fairly confident that there are relatively high windspeeds, regardless of whether I actually measure it or not...
What is SPL? Pressure, what is pressure? force/energy, which creates movement of air.

Bigger amounts of air moving is evidence of higher output levels.

Have you ever seen a car doing high numbers without moving any air? Granted with a car there are hundreds of other variables that may restrict the apparent movement of air and velocity of air, which is why some do better hairtricks/etc than others. Frequency also affects it. But when comparing same frequency, same car/setup, more air movement = louder, no?

I'm not arguing that you're moving air. Obviously a ported box will have airflow from the port.

However, you have no numbers to back up that you think you are moving MORE air in and out of the enclosure.

Have you ever seen a car doing high numbers with a big box and a gigantic port? Hell no, so think about stuff before you post.

More air does NOT mean a higher SPL reading. Take a look at assman's van. That thing moves an ASSTON of air, yet it won't meter as well as a pair of 10's in a crx. Explain that one to me mr. wizard.

Besides, port velocity is only one of MANY factors that determine whether a box will meter well. And actually, you want to maintain some pressure inside the enclosure. Having that large of a port (non-flared) will fail to do that.

Regardless, you are going completely beyond the realm of SPL physics with this test. Air movement out of the port is all fine and dandy, but scale that down into a vehicle and see if you get the same results. Getting high SPL is a combination of port velocity, sub movement, and the vehicle itself. You have one of the three. Better luck next time.

I got a pretty simple test to see what this box is actually doing. Put an SPL meter in front of the port. Find out what it reads. If you can do that, with a video, then I'll show you what my properly designed single 10" box does. That will end this train wreck of a thread.

 

[Rashaddd 5,000+ posts]

I'm not arguing that you're moving air. Obviously a ported box will have airflow from the port.
However, you have no numbers to back up that you think you are moving MORE air in and out of the enclosure.

Have you ever seen a car doing high numbers with a big box and a gigantic port? Hell no, so think about stuff before you post.

More air does NOT mean a higher SPL reading. Take a look at assman's van. That thing moves an ASSTON of air, yet it won't meter as well as a pair of 10's in a crx. Explain that one to me mr. wizard.

Besides, port velocity is only one of MANY factors that determine whether a box will meter well. And actually, you want to maintain some pressure inside the enclosure. Having that large of a port (non-flared) will fail to do that.

Regardless, you are going completely beyond the realm of SPL physics with this test. Air movement out of the port is all fine and dandy, but scale that down into a vehicle and see if you get the same results. Getting high SPL is a combination of port velocity, sub movement, and the vehicle itself. You have one of the three. Better luck next time.

I got a pretty simple test to see what this box is actually doing. Put an SPL meter in front of the port. Find out what it reads. If you can do that, with a video, then I'll show you what my properly designed single 10" box does. That will end this train wreck of a thread.

I understand all this for the most part. Granted, no numbers to back up any real SPL readings/etc...

further tests to come...more port area, as well as in a vehicle, and on a meter.

I don't understand why you choose to get hostile over this, again, all I'm doing is introducing my findings, and then backing them up with reasoning. You say you know better, great, educate me. I'm just exploring an extreme of box design and it's effects.

The other point of this was, audioholic made the statement numerous times in another thread that the amount of air radiating in the port is directly proportionate and equal to the amount the sub is displacing, which is clearly not true.

I don't mean to offend anyone...I'm simply discussing ideas. Hell, I'd love to talk on MSN or something about this too if anyone knowledgeable is up for it. Shoot me a pm.

If nothing else, I feel like a design with this concept in mind would have to do a nasty hairtrick relative to the amount of cone area/power.

 

[mobeious 10+ year member]

not hostile just this thread is a FAIL and makes no **** since

 

[Rashaddd 5,000+ posts]

not hostile just this thread is a FAIL and makes no **** since

It does make sense...even the other two seem to at least understand what I'm getting at, just dont agree that it's either A: relevant, or B: correct

 

[mobeious 10+ year member]

ur grammer is horrible i can hardly make out what ur saying lol

 

[ThatChevyGuy 5,000+ posts]

where do i buy those tubes?

How much are they?

 

[Rashaddd 5,000+ posts]

ur grammer is horrible i can hardly make out what ur saying lol

Are you serious? lol

 

[mobeious 10+ year member]

my spelling is horrible but ur sentences make no sense its like u miss words

 

[Rashaddd 5,000+ posts]

my spelling is horrible but ur sentences make no sense its like u miss words

I leave em out sometimes to shorten things, but who doesn't? Its called teh internet

 

[MikeyB 5,000+ posts]

No.

 

[tommyk90 5,000+ posts]

The other point of this was, audioholic made the statement numerous times in another thread that the amount of air radiating in the port is directly proportionate and equal to the amount the sub is displacing, which is clearly not true.

audioholic is correct to a point.

A sub is going to displace the same amount of air no matter the enclosure, given the same circumstances (mainly xmax). Now how that air comes OUT of the box is a whole different story. I think that is where the two of you disagree, and with merit I might add.

Like I said, put a meter at the end of that port and see what it does, then I'll show you what my single 10" box does. Numerical evidence far outweighs "this is what I think it means" evidence.

 

[Rashaddd 5,000+ posts]

audioholic is correct to a point.
A sub is going to displace the same amount of air no matter the enclosure, given the same circumstances (mainly xmax). Now how that air comes OUT of the box is a whole different story. I think that is where the two of you disagree, and with merit I might add.

Like I said, put a meter at the end of that port and see what it does, then I'll show you what my single 10" box does. Numerical evidence far outweighs "this is what I think it means" evidence.

Where is the delta of air if there is more air coming out of the port than being visibly moved by the sub? It would have to be pressure inside the box right? Would it be added pressure or lack thereof?

And I agree, if I had a meter on hand, I'd have had numbers before I even thought about posting any of this.